Problem: Simplify the following expression: $r = \dfrac{-80t - 100}{110}$ You can assume $t \neq 0$.
Explanation: Find the greatest common factor of the numerator and denominator. The numerator can be factored: $-80t - 100 = - (2\cdot2\cdot2\cdot2\cdot5 \cdot t) - (2\cdot2\cdot5\cdot5)$ The denominator can be factored: $110 = (2\cdot5\cdot11)$ The greatest common factor of all the terms is $10$ Factoring out $10$ gives us: $r = \dfrac{(10)(-8t - 10)}{(10)(11)}$ Dividing both the numerator and denominator by $10$ gives: $r = \dfrac{-8t - 10}{11}$